Conventionally, an electronic circuit that uses a power semiconductor or the like which operates a high electric power, such as an inverter circuit and a power supply circuit may be requested for a furthermore miniaturization corresponding to the miniaturization of equipment that uses such a circuit. It is also necessary that a heat dissipation of the power semiconductor which is mounted with a high-density for the miniaturization is efficiently performed in a low cost.
For example, in a control unit of rotating electrical machines such as a motor that is used to an electric power steering apparatus (EPS) which is used in a vehicle such as a car, the inverter circuit and a relay circuit comprise plural power semiconductors and so on. Accordingly, if these plural power semiconductors are integrated as a single module, it is possible to contribute the miniaturization of the overall electric power steering apparatus (EPS) together with the further miniaturization of the control unit.
On the other hand, as a package that is modularized these plural power semiconductors, for example, technologies that are described in Japanese Patent No. 4549884 B2 (Patent Document 1) and WO 12/127696 A1 (Patent Document 2) are disclosed.
In Patent Document 1, a semiconductor apparatus comprising an electrical conductive heat dissipating substrate; a semiconductor device which is directly disposed on the heat dissipating substrate; plural main electrode plates which each one ends thereof is electrically connected to a main electrode of the semiconductor device; and a resin package which resin-seals the heat dissipating substrate, the semiconductor device, and the plural main electrode plates, wherein external dimensions of the heat dissipating substrate are almost the same as those of the resin package, each the other ends of the plural main electrode plates is exposed to an external at a top surface-side, and the resin package is integral-molded by molding, is described. The surface of the mold package that is opposite to the surface which the semiconductor device is disposed on the electrical conductive heat dissipating substrate is thin molded, and a heat generation from the semiconductor device is heat-dissipated to a heatsink or the like that are attached to an exterior of the semiconductor apparatus via the heat dissipating substrate.
Further, in Patent Document 2, a power semiconductor module comprising plural first metal plates that are arranged on the same surface; power semiconductor chips that are mounted on the plural first metal plates; bridge-shape second metal plates that have bridge-guide sections and leg sections supporting the bridge-guide sections, and appropriately solder-joint between electrodes of the power semiconductor chips, and between the electrodes of the power semiconductor chips and the first metal plates with the leg sections; and a resin package that seals these members by an electrical insulating resin, wherein solder-joint sections of the leg sections are formed over a surface by a bending, and provided a position which are lower than the bridge-guide sections, is described.